title: Pure methotrexate encephalopathy presenting with seizures: CT and MRI features.
abstract: With the advent of chemotherapy, mortality rates in acute lymphoblastic leukaemia (ALL) have decreased, but complications in the central nervous system have appeared. These include direct involvement of the brain itself and the development of chemotherapy-related encephalopathy as a delayed reaction. In most reported cases, this encephalopathy is believed to be due to necrotising angiitis arising from the combination of chemotherapy with adjuvant radiotherapy. We report the cases of four children with ALL who had been treated with high-dose intravenous and intrathecal chemotherapy but no radiation therapy, and who were admitted to hospital because of seizures. CT of the brain revealed the presence of diffuse periventricular white matter hypodensities in all cases and subcortical hyperdense foci in three cases. MRI showed diffuse hyperintense white matter lesions on T2-weighted images in all four patients; hypointense changes were observed on susceptibility-sensitive FLASH sequences in the hyperdense foci seen on CT as well as changes that were hyperintense on T1-weighted images. It was, therefore, concluded that the lesions corresponded to a leukoencephalopathy with calcific deposits. These findings are of a pure form of methotrexate encephalopathy causing seizures.
authors.affiliation: Department of Neuroradiology, Institute of Diagnostic Radiology, Inselspital, University of Bern, CH-3010 Bern, Switzerland.
authors.forename: K
authors.initials: K
authors.lastname: Lövblad
authors.forename: P
authors.initials: P
authors.lastname: Kelkar
authors.forename: C
authors.initials: C
authors.lastname: Ozdoba
authors.forename: G
authors.initials: G
authors.lastname: Ramelli
authors.forename: L
authors.initials: L
authors.lastname: Remonda
authors.forename: G
authors.initials: G
authors.lastname: Schroth
mesh_terms: D000970:Antineoplastic Agents / Q000009:adverse effects*; D001921:Brain / Q000000981:diagnostic imaging / Q000473:pathology*; D001927:Brain Diseases / Q000139:chemically induced* / Q000000981:diagnostic imaging / Q000473:pathology*; D002114:Calcinosis / Q000139:chemically induced; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008727:Methotrexate / Q000009:adverse effects*; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000188:drug therapy*; D012640:Seizures / Q000139:chemically induced*; D014057:Tomography, X-Ray Computed
chemical_list: D000970:Antineoplastic Agents; D008727:Methotrexate